Conventionally, an evaporator of an air conditioner for a vehicle includes: a tube through which a refrigerant flows; and a fin which is joined to the tube to increase a heat exchange area between air flowing around the tube and the refrigerant (for example, see Patent Literature 1).
In such an evaporator, when a surface temperature falls below a freezing point, a freeze fracture possibly occurs, in which condensed water adhered to a surface of the evaporator freezes, causing volume expansion and fractures of the peripheral tube and the peripheral fin.
To handle this, temperature control of the evaporator is executed by using a thermistor in the conventional air conditioner for a vehicle. Accordingly, when a temperature of the evaporator becomes a reference temperature or lower, a refrigeration cycle is stopped, or a heat load is reduced. In this way, the condensed water that is adhered to the surface of the evaporator does not freeze, or the condensed water only freezes to such an extent that the freeze fracture does not occur.